Readers' comments

This story reminded me immediately of the 1951 movie, "No Highway in the Sky". Starring Jimmy Stewart, Marlene Dietrich and Glynis Johns, it's the story of an aircraft engineer (Stewart) who fears that a new plane -- the one he is flying in -- will shake apart and crash. Maybe, for safety's sake, planes should feature the new Slater-Slide.

Good luck getting it working. I've seen this technology hyped several times and we've tested it (not on aircraft but on other machines).

The basic problem is that you are looking for a tiny noise of a specific frequency in amongst a huge amount of other noise. Not only that but the crack noise does not occur continuously only at somewhat random intervals.

In our testing we found that even with modern signal processing and mounting sensors very close to the crack site, the amplitudes of the crack propagation were too low to be detectable and isolatable from the background noise.

We tried it again this year and were paid significant sums by a multinational company to try to get it to work. Again it was found that the crack noise amplitudes were simply too low to be useful.

This is so good and exhilarating. The advanced technology will, absolutely, make its contribution to decreasing oppotunities of unexpected cracks and guarantee a higher safety for passengers.
And I think,there will appear more advanced, efficient methods and devices to do the monitoring at some future date, instead of ending with the Asis.
But I have a strong hope that there will be air jackets and parachutes prepared for everyone in the air all over the world.as you know ,this service is available only in some flight courses.do you think the idea is excessive? in my opinion,airline companies may spend money on providing these survival equipments rather than compensation for injuries and deaths when air crash happens. Maybe I'm a fussy creature,since airoplane has the lowest probability of accident in the world.

It may well be that friction-stir welding may be a superior method of joining these materials together since the weld itself is stronger than the material joined, and it provides a much broader surface area by which to transmit and withstand tension and compression forces.

I'm surprised you didn't mention the ancient bombers still being flown by The US and Russia. The American B-52, for instance, first flew in the early 1950's. Although The current flying examples date from the 1960's, they are expected to continue operating until mid-century, almost 100 years of service. One could only wish their car could last that long.

this technology has been around for a while in the offshore industry where fatigue issues also often arise. As I recall it, the most critical part of the technology is building up an acoustic signature of the structure.

A pilot told me years ago that when they allowed smoking on flights you could see the nicotine stains which had crept through the invisible cracks and this was the most effective system of detection. Cheaper, too.

This approach, using sound and vibration analysis possibly in real-time to monitor aircraft integrity, really signals the aggregation of advancements in many fields of science and engineering from compact computing power and signal processing to microsensor manufacturing; not to mention the ability to build unheard of businesses around such technologies. In the late eighties on of my first tech product development and marketing projects was the launch of holographic interferometry systems for detecting cracks and failure points in aircraft parts and specific areas of fuselage. I'm sure the holographic systems still work quite well, but I can't imagine using them as real-time, inflight detection systems.

I think this is a great advance and another sign that there's still much opportunity for tech innovation and new business creation, despite the macro-economic woes. Perhaps if we focus on the opportunities and the emerging ways to create value, we'll both help recovery over the next few years and be benficiaries of it.